Microsoft Mouse Phone?

Just when you thought you had heard every concept that was attempting to integrate X into a cell phone, Microsoft throws out another wild card. In a recent patent application, the Big Bad M has put together what is essentially a phone (with screen and keypad on one side), and a way to operate your computer (via touchpad) on the back. From the patent: “[It’s a] system that facilitates navigating on a display, comprising: a mouse engine component that detects a location; and an interface component that integrates the mouse engine into a handheld communication device.” Now, the design could be used to navigate on the phone, but obviously would require a much bigger screen than the picture in the patent application to be effective. Does the future of the handheld computer rest on this kind of technology?